Protein microspheres for pulmonary drug delivery

Abstract

A new supercritical fluid (SCF) technique was developed for the preparation of microspheres for pulmonary drug delivery (PDD). This technique, based on the anti-solvent process, has incorporated advanced engineering design features to enable improved control of the particle formation process. Human recombinant insulin (HRI) was used as a model compound to evaluate the efficiency of this SCF process. An aqueous solution of HRI with a co-solvent was sprayed into high pressure carbon dioxide that extracted the solvent and water, leading to a dry fine powder with good particle size distribution and near ideal morphology for pulmonary drug delivery.